Edge holding and forming device eos sheet-glass machines



Aug. 5 1 24. 1,503,608

'H. e. SLJNGLUFF EDGE HOLDING AND FORMING DEVICE FOR SHEET GLASS MACHINES Fild June 5, 1923 :5 Sheets-Shet 1 Aug: 5 924. 1,503,608

* 1 H. SLINGLUFF EDGE HOLDING AND F QRMING DEVICE FOR SHEET GLASS MACHINES Filed June s. 1933 I .s Sheets-Sheet 2 M/vewme Aug. 5 1924.

' H. G. SLINGLUFF EDGE HOLDING AND FORMING DEVICE FOR SHEET GLASS MACHINES Filed June 5, 1923 3 Sheets-Sheet 5 FIB--5.

Patented Aug. 5, 1924.

UNITED STATES PATENT OFFICE.

HARRY G. SLINGLUFF, 0F MOUNT VERNON, OHIO, ASSIGNOR TO PITTSBURGH PLATE GLASS COMPANY, A

CORPORATION 01] PENNSYLVANLA.

EDGE HOLDING AND FOEMING DEVICE FOR SHEET-GLASS MACHINES.

Application filed June 5,

To all whom it may concern:

Be it known that I, HARRY G. SLINGLUFF, a citizen of the United States, and a resi dent of Mount Vernon, in the county of Knox and State of Ohio, have made a new and useful invention in Improvements in Edge Holding and Forming Devices for Sheet-Glass Machines, of which the following is a specification.

The invention relates to apparatus for use with a sheet glass drawing machine. The invention has for its objects the provision of means for rendering the anchorage of the base of the sheet at its edge more secure, and the provision ofv means for improving the edge of the sheet rendering it softer and free from roughness or cracks tending to cause breakage. Briefly stated, the first of these objects is accomplished by applying chilling means preferably jets of air, to the glass bath at the points of anchorage, and the second object is accomplished by applying heat, preferably by means of gas flames, to the edges of the sheet immediately above the stripping fingers. One embodiment of the invention is illustrated in the accompanying drawings wherein:

Figure 1 is a diagrammatic side elevation showing the drawing apparatus with which the edge holding device is preferably used, such drawing device being shown and described in detail in my pending application Serial No. 621,184.. 2 is a transverse section through one side of the drawing tank showing the device in side elevation. Fig. 3 is an end elevation of the apparatus of Fig. 2. Fig. 4; is a perspective view of a part of the construction. And Fig. 5 is a View similar to that of Fig. 2 showing a modification.

1 is the drawing tank or extension carrying a molten bath of glass 2 in communication with a suitable melting tank, not shown; 3 and 4 are endless belts, preferably of asbestos fabric for continuously draw ing the sheet of glass 5 from the molten bath; 6 and 7 are the driving pulleys for the belts, such belts being driven from a suitable motor, not shown; 8 and 9 are solid steel bars circular in cross section lying in the lower ends of the belts and serving by reason of their weight to hold the belts in tension; 10 are a series of rolls back of the 1923. Serial No. 6%,496.

inner flights of the belts for pressing the belts against the glass, such rolls being yieldingly held inward by means of springs or weights, not shown; 11 and 12 are pairs of driven rolls covered with asbestos for assisting in the pulling of the sheet; and 13 is one of the edge holding and forming devices to which the present invention is particularly directed, it being understood that such edge holding devices may be used in connection with any form of drawing mechanism, although the one as illustrated and described is preferred.

It will be understood that an edge holding device, such as that shown in Fig. 2 is applied at each side of the sheet, but for brevity of description and illustration only one of such devices is shown. The device in its preferred form consists of a plate 14 formed at its end into the stripping fingers 15 and having a pair of anchoring posts 16 which project downwardly into the glass as indicated in Fig. 2. The plate at its rear end is secured to a rack bar 17 bv means of the bracket 18 and the rack bar is mounted for longitudinal movement in the casing 19 and is moved in and out by means of a pair of gears mounted on the shafts 20 and operated by means of a worm secured to the hand wheel 21, the purpose being to provide an in and out adjustment of the plate 14:, and the adjusting means descril ed being that of a well known automobile jack. The casing 19 is secured by means of the bracket 22 t0 the vertically movable rack bar 23' mounted in the casing 24:. This rack bar is moved from the hand wheel 25 by means of mechanism corresponding to that above described for giving the horizontal movement of the rack bar 17. The casing 14 is mounted upon asuitable standard or base 25. By means of this construction, the plate and the edge holding and forming devices carried thereby may be readily given adjustments in any desired direction in order to meet requirements.

The posts 16 serve to anchor the edge of the sheet at its base and prevent inward movement thereof during the drawing action. Before positioning the tool, the posts are preferably heated, so that an immediate adherence of the glass thereto is secured. In order to still further increase the viscosity of the glass adjacent the posts so that the attachment may be more secure, provi sion is made "for chilling the glass just behind the posts. This is acconmlished by means of a pipe 26 secured to the plate 1 1: and connected to a suitable source of supply. The inner end of this pipe projects downwardly through the plate as indicated at 27 so that air is applied immediately be hind the posts. The cooling as provided by this air supply serves to stitien up the surface of the glass and promotes the attachment of the surface glass from the edge of the sheet to the posts and to the side wall of the furnace.

The fingers 15 are spaced apart as ind cated in Fig. 1, so that their inner edges c--- gage the sides of the tapering portion ot the sheet and tend to thin it as it is drawn upward therethrough. In som periods ot the operation these fingers may touch the the glass only lightly or not at all, but in other periods the edges tend to draw too thick and at this time the tingers come into play to thin the sheet and maintain it at a uniform thickness. Under ordinary conditions the chilling eil ect ot the device including the action of the metal upon the edge and the supply of air through the pipe 2c is such as to harden the edge ot the sheet to too great a degree. This hardening tends to promote breakage and roughness due to the scraping action of the fingers 15 on the edge ot' the glass, and in order to remedy this condition heating means are plOVlilCil just above the stripping fingers. heee heat ing means are preferably in the form ot a pair of gas burners .28 bent in the tor in i.ndi-- cated in Figs. 2 and +t, and i.'ovided with perforations 29 along their inner sides so as to direct the gas from the burners against the sides of the sheet at its edge. 'i hese burners are supplied by means or" the pipe 30 secured to the plate 1.4:.

Fig. 5 illustrates a modification in which the plate 31 provided with the fingers 353 corresponds in construction and function with the parts 14: and 15 of the Fig. construction, the plate also being similarly supported for adjustment. In this construction. however, the posts 1:; of Fig. 2 are omitted and in place thereof, the projection 33 on the clay guide bar 34 is substituted. This projection is brought up to or adjacent the surface of the glass and the base. of the glass becomes anchored thereto, thus tending to prevent inward movement of the sheet in the same manner as the posts 16 of Fig. 2 prevent inward movement. Various other means might be employed "for anchoring the edge of the sheet, and the confio'rn'ation ot the stripping ting s might also he chanc d to meet varying requirements. In some c es it may not be necessary to chill the surf of the glass adjacent the anchoring means, or to heat the edge of the sheet above the lingers, but ordinarily 1 have found that these details of construction or their equivalent wcre necessary in order to secure a pern'ianent anchorage ot the edge of the sheet and in order to produce an edge which is uniformly smooth and sott. It will be apparent tha' the invention is not limited to chilling the surtace of the glass by means of an air blast or to heating the edge of the sheet by means of gas burners, a variety of means being known in the art for accomplishing both these functions, although the devices employed are regarded as the simplest, cheapest, and most conveniently applied. It is possible to anchor the edge of the sheet directly to the wall of the furnace, in which case such wall constitutes the means for anchoring the base of the sheet," but preferably the edge of the sheet is more remote from the wall of the furnace, as illustrated in Fig. 1, and other anchoring means, such as the posts 16 are employed between the furnace wall and the edge of the sheet. in order to regulate the temperature of the bath atthe edge. of the sheet, one of the posts 16 is preferably made hollow to receive the thermal couple 16 connected by the wires 16" to a suitable indicating device.

What I claim is:

1. In comoination in apparatus for drawing a glass sheet from a molten bath, means for anchoring the base of the sheet in the bath at its edge, a pair of stripping fingers spaced apart above the base of the sheet so that they straddle said edge and thin it, and means tor applyinghcat to the edge above the fingers.

33. In combination in apparatus for drawin a gt. sheet from a molten bath, means ior anchoring the base of the sheet in the bath at its edge, a pair of stripping fingers spaced apart above the base of the sheet so that they straddle said edge and thin it, means for chilling the glass adjacent the anchorage of its edge, and means for applyheat to the edge above the fingers.

3. In combination in apparatus "for drawing a glass sheet from a molten bath, means for anchoring the base of the sheet in the bath at its edge, a pair of stripping fingers spaced apart above the base of the sheet so that they straddle said edge and-thin it means for directing a flow of air against the surface oi the glass opposite the edge of the sheet, and means for applying heat to the edge above the fingers.

4-. In combination in apparatus for drawa glass sheet from a molten bath, means or anchor. the base-0t the sheet in the bath at its edge, a pair of stripping fingers spaced ap t above the base of the sheet so that they straddle said edge and thin it, and

means for directing e flow of air against the surfaee of the glass bath opposite the edge of the sheet.

In combination in Apparatus for drawing a glass sheet, means "for anchoring the base comprising a post projecting down into the bath at its edge, a pair of stripping members spaced apart above the base of the sheet, and temperature indicating means ezurried in said post. 10

In testimony whereof, I have hereunto subscribed my name this 25th day of hltuy, 1923.

HARRY SLINGLUFF. 

